/* ChibiOS/RT - Copyright (C) 2006,2007,2008,2009,2010, 2011,2012 Giovanni Di Sirio. This file is part of ChibiOS/RT. ChibiOS/RT is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 3 of the License, or (at your option) any later version. ChibiOS/RT is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program. If not, see . --- A special exception to the GPL can be applied should you wish to distribute a combined work that includes ChibiOS/RT, without being obliged to provide the source code for any proprietary components. See the file exception.txt for full details of how and when the exception can be applied. */ /** * @file pwm.h * @brief PWM Driver macros and structures. * * @addtogroup PWM * @{ */ #ifndef _PWM_H_ #define _PWM_H_ #if HAL_USE_PWM || defined(__DOXYGEN__) /*===========================================================================*/ /* Driver constants. */ /*===========================================================================*/ /** * @name PWM output mode macros * @{ */ /** * @brief Standard output modes mask. */ #define PWM_OUTPUT_MASK 0x0F /** * @brief Output not driven, callback only. */ #define PWM_OUTPUT_DISABLED 0x00 /** * @brief Positive PWM logic, active is logic level one. */ #define PWM_OUTPUT_ACTIVE_HIGH 0x01 /** * @brief Inverse PWM logic, active is logic level zero. */ #define PWM_OUTPUT_ACTIVE_LOW 0x02 /** @} */ /*===========================================================================*/ /* Driver pre-compile time settings. */ /*===========================================================================*/ /*===========================================================================*/ /* Derived constants and error checks. */ /*===========================================================================*/ /*===========================================================================*/ /* Driver data structures and types. */ /*===========================================================================*/ /** * @brief Driver state machine possible states. */ typedef enum { PWM_UNINIT = 0, /**< Not initialized. */ PWM_STOP = 1, /**< Stopped. */ PWM_READY = 2, /**< Ready. */ } pwmstate_t; /** * @brief Type of a structure representing a PWM driver. */ typedef struct PWMDriver PWMDriver; /** * @brief PWM notification callback type. * * @param[in] pwmp pointer to a @p PWMDriver object */ typedef void (*pwmcallback_t)(PWMDriver *pwmp); #include "pwm_lld.h" /*===========================================================================*/ /* Driver macros. */ /*===========================================================================*/ /** * @name PWM duty cycle conversion * @{ */ /** * @brief Converts from fraction to pulse width. * @note Be careful with rounding errors, this is integer math not magic. * You can specify tenths of thousandth but make sure you have the * proper hardware resolution by carefully choosing the clock source * and prescaler settings, see @p PWM_COMPUTE_PSC. * * @param[in] pwmp pointer to a @p PWMDriver object * @param[in] denominator denominator of the fraction * @param[in] numerator numerator of the fraction * @return The pulse width to be passed to @p pwmEnableChannel(). * * @api */ #define PWM_FRACTION_TO_WIDTH(pwmp, denominator, numerator) \ ((uint16_t)((((uint32_t)(pwmp)->period) * \ (uint32_t)(numerator)) / (uint32_t)(denominator))) /** * @brief Converts from degrees to pulse width. * @note Be careful with rounding errors, this is integer math not magic. * You can specify hundredths of degrees but make sure you have the * proper hardware resolution by carefully choosing the clock source * and prescaler settings, see @p PWM_COMPUTE_PSC. * * @param[in] pwmp pointer to a @p PWMDriver object * @param[in] degrees degrees as an integer between 0 and 36000 * @return The pulse width to be passed to @p pwmEnableChannel(). * * @api */ #define PWM_DEGREES_TO_WIDTH(pwmp, degrees) \ PWM_FRACTION_TO_WIDTH(pwmp, 36000, degrees) /** * @brief Converts from percentage to pulse width. * @note Be careful with rounding errors, this is integer math not magic. * You can specify tenths of thousandth but make sure you have the * proper hardware resolution by carefully choosing the clock source * and prescaler settings, see @p PWM_COMPUTE_PSC. * * @param[in] pwmp pointer to a @p PWMDriver object * @param[in] percentage percentage as an integer between 0 and 10000 * @return The pulse width to be passed to @p pwmEnableChannel(). * * @api */ #define PWM_PERCENTAGE_TO_WIDTH(pwmp, percentage) \ PWM_FRACTION_TO_WIDTH(pwmp, 10000, percentage) /** @} */ /** * @name Macro Functions * @{ */ /** * @brief Changes the period the PWM peripheral. * @details This function changes the period of a PWM unit that has already * been activated using @p pwmStart(). * @pre The PWM unit must have been activated using @p pwmStart(). * @post The PWM unit period is changed to the new value. * @note If a period is specified that is shorter than the pulse width * programmed in one of the channels then the behavior is not * guaranteed. * * @param[in] pwmp pointer to a @p PWMDriver object * @param[in] period new cycle time in ticks * * @iclass */ #define pwmChangePeriodI(pwmp, period) { \ (pwmp)->period = (period); \ pwm_lld_change_period(pwmp, period); \ } /** * @brief Enables a PWM channel. * @pre The PWM unit must have been activated using @p pwmStart(). * @post The channel is active using the specified configuration. * @note Depending on the hardware implementation this function has * effect starting on the next cycle (recommended implementation) * or immediately (fallback implementation). * * @param[in] pwmp pointer to a @p PWMDriver object * @param[in] channel PWM channel identifier (0...PWM_CHANNELS-1) * @param[in] width PWM pulse width as clock pulses number * * @iclass */ #define pwmEnableChannelI(pwmp, channel, width) \ pwm_lld_enable_channel(pwmp, channel, width) /** * @brief Disables a PWM channel. * @pre The PWM unit must have been activated using @p pwmStart(). * @post The channel is disabled and its output line returned to the * idle state. * @note Depending on the hardware implementation this function has * effect starting on the next cycle (recommended implementation) * or immediately (fallback implementation). * * @param[in] pwmp pointer to a @p PWMDriver object * @param[in] channel PWM channel identifier (0...PWM_CHANNELS-1) * * @iclass */ #define pwmDisableChannelI(pwmp, channel) \ pwm_lld_disable_channel(pwmp, channel) /** @} */ /*===========================================================================*/ /* External declarations. */ /*===========================================================================*/ #ifdef __cplusplus extern "C" { #endif void pwmInit(void); void pwmObjectInit(PWMDriver *pwmp); void pwmStart(PWMDriver *pwmp, const PWMConfig *config); void pwmStop(PWMDriver *pwmp); void pwmChangePeriod(PWMDriver *pwmp, pwmcnt_t period); void pwmEnableChannel(PWMDriver *pwmp, pwmchannel_t channel, pwmcnt_t width); void pwmDisableChannel(PWMDriver *pwmp, pwmchannel_t channel); #ifdef __cplusplus } #endif #endif /* HAL_USE_PWM */ #endif /* _PWM_H_ */ /** @} */